"There is no grace, no skill, and no intellect behind these attacks. You are not a hacker and you do not deserve respect for your childish actions," it said.

"You are no better than the twisted individuals who spray a crowd of innocent bystanders with a machine gun, only to nick your intended target."

Hackers are keen to distance themselves from those who seek to create havoc on the internet. They argue they are motivated by intellectual stimulation rather than profit or malice.

"If you can't express yourself better than a saturation attack, and can't deal with being called a name or wronged somehow, seek help offline. You sorely need it," said the Hacker News Network article.

No special knowledge

The cyber assaults were mounted using software readily available over the internet which allows someone to send huge amounts of information to a computer system, overloading it.

Monday

Yahoo

Tuesday

CNN

Amazon

eBay

Buy.com

Wednesday

E*Trade

Datek

ZDNet

For hackers, this sort of attack, called a Denial of Service, requires no special programming knowledge.

But some security experts have warned that the nature of the raids suggests a well-organised and sophisticated group at work.

An e-mail from Yahoo engineers said the vandals knew what servers to target to cause the maximum disruption.

It described the Yahoo attackers as "smart and above your average script-kiddie," saying they "probably know both Unix and networking pretty well and learn about site topology to find weak spots."

In the hacking underground, technically-skilled but often alienated individuals earn respect of their peers by showing flashes of brilliance in exposing the vulnerability of a computer system.

Most hackers are anonymous, known only by their internet monikers.

Perhaps the most famous is Kevin Mitnick. A legend in hacker circles, he once headed the FBI's most wanted list.

He has just been released from jail, following a five-year prison sentence for a series of high-profile break-ins into the systems of, among others, Motorola, Nokia, Fujitsu, Novell, NEC, and Sun Microsystems.

Some in the hacking community have also rounded on the media over their reporting of the attacks, saying it is unfair to point the finger at hackers.

"We cannot permit them or anyone else to lay the blame on hackers," said the front page of one of the main hacking publication on the internet, 2600 Magazine.

"So far, the corporate media has done a very bad job covering this story, blaming hackers and in the next sentence admitting they have no idea who's behind it."